Intersection of two json files

Question

I have two JSON arrays with same fields as follows:

var total_90 = [
    { "date": "2011-11-14T17:22:59Z", "quantity": 2, "total": 90, "tip": 0, "type": "tab" },
    { "date": "2011-11-14T17:07:21Z", "quantity": 2, "total": 90, "tip": 1, "type": "tab" },
    { "date": "2012-11-14T16:30:43Z", "quantity": 3, "total": 90, "tip": 0, "type": "tab" }
];

var tip_0 = [
    { "date": "2011-11-14T17:22:59Z", "quantity": 2, "total": 80, "tip": 0, "type": "tab" },
    { "date": "2011-11-14T17:07:21Z", "quantity": 2, "total": 70, "tip": 0, "type": "tab" },
    { "date": "2011-11-14T16:58:03Z", "quantity": 2, "total": 90, "tip": 0, "type": "tab" },
    { "date": "2011-11-14T16:30:43Z", "quantity": 2, "total": 90, "tip": 0, "type": "tab" }
];

I need a third JSON file which has the intersection of the above two JSON files. (By intersection, I mean all the rows from both the JSON files which have TOTAL=90 AND TIP=0) Is there some way to do this?

My expected output will be a third JSON file with the following output

{"date":"2012-11-14T16:30:43Z","quantity":3,"total":90,"tip":0,"type":"tab"},
{"date":"2011-11-14T16:58:03Z","quantity":2,"total":90,"tip":0,"type":"tab"},
{"date":"2011-11-14T16:30:43Z","quantity":2,"total":90,"tip":0,"type":"tab"}

Possible duplicate of [Merging two json array object based on union and intersection](http://stackoverflow.com/questions/37304104/merging-two-json-array-object-based-on-union-and-intersection) — Paul Sweatte, Jan 30 '17 at 21:25

score 0 · Answer 1 · edited May 23 '17 at 11:53

0

You need to loop the 2 objects and merge the contents into 1 object.

For examples check this thread since this is a duplicate How can I merge properties of two JavaScript objects dynamically?

edited May 23 '17 at 11:53

Community

1
1

answered May 22 '14 at 07:04

JohanSellberg

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score 0 · Answer 2 · answered Jan 07 '19 at 13:57

You could do the following to collect all the rows from both the JSON files which have TOTAL = 90 and TIP = 0 -

var total_90 = [
    { "date": "2011-11-14T17:22:59Z", "quantity": 2, "total": 90, "tip": 0, "type": "tab" },
    { "date": "2011-11-14T17:07:21Z", "quantity": 2, "total": 90, "tip": 1, "type": "tab" },
    { "date": "2012-11-14T16:30:43Z", "quantity": 3, "total": 90, "tip": 0, "type": "tab" }
];

var tip_0 = [
    { "date": "2011-11-14T17:22:59Z", "quantity": 2, "total": 80, "tip": 0, "type": "tab" },
    { "date": "2011-11-14T17:07:21Z", "quantity": 2, "total": 70, "tip": 0, "type": "tab" },
    { "date": "2011-11-14T16:58:03Z", "quantity": 2, "total": 90, "tip": 0, "type": "tab" },
    { "date": "2011-11-14T16:30:43Z", "quantity": 2, "total": 90, "tip": 0, "type": "tab" }
];

// An empty arrays to contain final intersection array
var result = [];

/* now looping over both arrays to traverse all the elements from them */

// iterating over first array
total_90.forEach(x => {
    // iterating over second array
    tip_0.forEach(y => {
        // push into output array only if total is 90 & tip is 0
        if ((x.total == 90 && y.total == 90) && (x.tip == 0 && y.tip == 0)) {
            result.push({
                date: x.date,
                quantity: x.quantity,
                total: x.total,
                tip: x.tip,
                type: x.type
            });
        }
    });
});

console.log(result);

Note - this can be optimized to reduce the time complexity.

score -1 · Answer 3 · answered May 22 '14 at 06:51

var total_90 = [
{"date":"2011-11-14T17:22:59Z","quantity":2,"total":90,"tip":0,"type":"tab"},
{"date":"2011-11-14T17:07:21Z","quantity":2,"total":90,"tip":1,"type":"tab"},
{"date":"2012-11-14T16:30:43Z","quantity":3,"total":90,"tip":0,"type":"tab"}
              ]

var tip_0 = [
{"date":"2011-11-14T17:22:59Z","quantity":2,"total":80,"tip":0,"type":"tab"},
{"date":"2011-11-14T17:07:21Z","quantity":2,"total":70,"tip":0,"type":"tab"},
{"date":"2011-11-14T16:58:03Z","quantity":2,"total":90,"tip":0,"type":"tab"},
{"date":"2011-11-14T16:30:43Z","quantity":2,"total":90,"tip":0,"type":"tab"}
            ] 

allData['total_90'] = total_90;
allData['tip_0'] = tip_0;

use allData

-1 This only gives an allData object with the 2 objects not the objects merged into 1. — JohanSellberg, May 22 '14 at 07:02

jhyap · Accepted Answer · 2014-05-22T12:15:15.363

function intersection(a, b)
{
  var result = [];

       for (var i = 0; i < a.length; i++){
            if (a[i].total == 90 && a[i].tip == 0)
            {

                result.push(a[i]);
            }
        }

       for (var i = 0; i < b.length; i++){
            if (b[i].total == 90 && b[i].tip == 0)
            {
                result.push(b[i]);
            }
        }
    return result;
}

JSFiddle

EDIT: Update the function with the use of concat to provide a slightly more short hand.

function intersection(a, b)
{
  var result = [];

    var c = a.concat(b);


       for (var i = 0; i < c.length; i++){
            if (c[i].total == 90 && c[i].tip == 0)
            {

                result.push(c[i]);
            }
        }

    return result;
}

New JSFiddle

can you take a look at this? http://stackoverflow.com/questions/23827030/cross-filter-using-drop-downs — Nisha Singh, May 23 '14 at 10:40

Intersection of two json files

4 Answers4